Struct LongEccHeader 

pub struct LongEccHeader { /* private fields */ }

The 32-byte header of a long ECC codeword.

Records the codec geometry (error-correction capability, overlap factor, and lengths) and the payload checksum, and is itself protected by a dedicated checksum and parity bytes.

Implementations

impl LongEccHeader

pub const fn checksum(&self) -> u64

Returns the XXH64 checksum of the message and parity bytes.

impl LongEccHeader

pub fn from_byte_slice( bytes: &[u8], ) -> Result<Self, LongEccHeaderFromByteSliceError>

Parses a header from the first 32 bytes of a slice.

Errors

Returns InsufficientBytes if bytes holds fewer than 32 bytes, or a LongEccHeaderFromBytesError if parsing the header fails.

impl LongEccHeader

pub fn from_bytes(bytes: [u8; 32]) -> Result<Self, LongEccHeaderFromBytesError>

Parses a header from its serialized form, correcting errors via the header parity.

Errors

Returns an error if header correction fails, or if the corrected header carries an incorrect magic number, version, or checksum, a message length that does not fit within the full length, an invalid segment-to-parity ratio, or a full length that does not match the derived codeword length.

impl LongEccHeader

pub const fn full_length(&self) -> u32

Returns the length of the full codeword, including the header and parity.

impl LongEccHeader

pub const fn header_checksum(&self) -> u32

Returns the checksum protecting the header fields, folded to 32 bits.

impl LongEccHeader

pub const fn header_parity(&self) -> [u8; 8]

Returns the parity bytes protecting the header itself.

impl LongEccHeader

pub const fn last_segment_length(&self) -> u8

Data length of the final ECC segment, always shorter than segment_length.

The constructors enforce 2 * parity < segment_distance, so the subtraction cannot underflow.

impl LongEccHeader

pub const fn magic(&self) -> u16

Returns the magic number identifying a long ECC header.

impl LongEccHeader

pub const fn message_length(&self) -> u32

Returns the length of the encoded message.

impl LongEccHeader

pub fn new( parity: u8, overlap_factor: OverlapFactor, full_length: u32, message_length: u32, checksum: u64, ) -> Result<Self, LongEccHeaderConstructorError>

Constructs a header, computing its checksum and parity.

Errors

Returns InvalidParityCount if parity exceeds MAX_PARITY, InvalidMessageLength if the header and message do not fit within full_length, InvalidSegmentParityRatio if the parity bytes leave no room for new data within a segment, InvalidFullLength if full_length does not match the codeword length derived from the message length and segment geometry, or GenerateParity if generating the header parity fails.

impl LongEccHeader

pub const fn overlap_factor(&self) -> OverlapFactor

Returns the overlap factor: the approximate number of codewords covering each byte.

impl LongEccHeader

pub const fn parity(&self) -> u8

Returns the error-correction capability per segment: the number of byte errors each segment can recover from.

impl LongEccHeader

pub const fn parity_bytes(&self) -> u8

Returns the number of parity bytes per segment: 2 * parity, two per correctable error.

impl LongEccHeader

pub const fn segment_count(&self) -> u32

Number of segments: every segment before the last contributes segment_distance - 2 * parity new data bytes, and the final, shorter segment covers the remainder.

The constructors enforce 2 * parity < segment_distance, so the subtraction cannot underflow.

impl LongEccHeader

pub const fn segment_distance(&self) -> u8

Stride between consecutive segment starts: segment_length divided by the overlap count, rounded down, so segments cover each byte approximately overlap_factor times.

impl LongEccHeader

pub const fn segment_length(&self) -> u8

Usable data bytes per 255-byte segment: 255 minus the 2 * parity parity bytes.

impl LongEccHeader

pub fn to_bytes(self) -> [u8; 32]

Serializes the header into its 32-byte wire format.

impl LongEccHeader

pub const fn version(&self) -> u8

Returns the encoding version number.

Trait Implementations

impl Clone for LongEccHeader

fn clone(&self) -> LongEccHeader

Returns a duplicate of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Copy for LongEccHeader

impl Debug for LongEccHeader

fn fmt(&self, f: &mut Formatter<'_>) -> Result

Formats the value using the given formatter.

impl Eq for LongEccHeader

impl Hash for LongEccHeader

fn hash<__H: Hasher>(&self, state: &mut __H)

Feeds this value into the given Hasher.

fn hash_slice<H>(data: &[Self], state: &mut H)

where H: Hasher, Self: Sized,

Feeds a slice of this type into the given Hasher.

impl Ord for LongEccHeader

fn cmp(&self, other: &LongEccHeader) -> Ordering

This method returns an Ordering between self and other.

fn max(self, other: Self) -> Self

where Self: Sized,

Compares and returns the maximum of two values.

fn min(self, other: Self) -> Self

where Self: Sized,

Compares and returns the minimum of two values.

fn clamp(self, min: Self, max: Self) -> Self

where Self: Sized,

Restrict a value to a certain interval.

impl PartialEq for LongEccHeader

fn eq(&self, other: &LongEccHeader) -> bool

Equality operator ==.

fn ne(&self, other: &Rhs) -> bool

Inequality operator !=.

impl PartialOrd for LongEccHeader

fn partial_cmp(&self, other: &LongEccHeader) -> Option<Ordering>

This method returns an ordering between self and other values if one exists.

fn lt(&self, other: &Rhs) -> bool

Tests less than (for self and other) and is used by the < operator.

fn le(&self, other: &Rhs) -> bool

Tests less than or equal to (for self and other) and is used by the <= operator.

fn gt(&self, other: &Rhs) -> bool

Tests greater than (for self and other) and is used by the > operator.

fn ge(&self, other: &Rhs) -> bool

Tests greater than or equal to (for self and other) and is used by the >= operator.

impl StructuralPartialEq for LongEccHeader